These studies are concerned with the role of beta-alanine and, secondarily, dopamine in melanization, metabolism, behavior, and behavioral mechanisms involved in maintaining melanistic polymorphism shown by wild populations of Drosophila melanogaster in northern Indiana and elsewhere. Autoradiographic micrography is used in attempts to determine possible relationships between beta-alanine and structure, particularly as related to mechanisms of regulation of growth and glucose catabolism. BIBLIOGRAPHIC REFERENCE: Jacobs, M.E. 1976. Binding of beta-alanine, dopamine, and dopa 1-C-14 by normal, ebony, and dark Drosophila melanogaster cuticles. J. Insect Physiol. 6.